The Queen’s income from her private Duchy of Lancaster estate has risen by almost a fifth to £16 million.
The money the Queen receives from the Duchy is used to fund her public and private activities.
It rose by 18%, increasing by £2.4 million on last year, accounts for the year ending March 2015 showed.
The total capital value of the Duchy, a portfolio of land, property and assets held in trust for the Sovereign, has risen by almost 7% to £472.1 million.
The estate is not subject to corporation tax as it is not a separate legal entity for tax purposes, but the Queen voluntarily pays income tax on revenue she receives from the Duchy.
The report stated: “The strong performance for the year has been spread across all the portfolios.
“Last year we continued to see a significant amount of structural change within the Duchy.
“Work continues to improve the controls and processes throughout the organisation and to ensure that the focus on individual business areas is enhanced.
“The results for the year show a willingness to buy when the appropriate opportunities arise, and at the same time, to take advantage of the low interest rate environment.”
Accounts released last month showed the monarchy cost the taxpayer £35.7 million for the second year running – the equivalent of 56p for each person in the country.
The cost of travel increased by almost £1 million during 2014/15 compared with the previous year but overall royal household expenditure remained the same.